By: Suzanne Kane, October 13th, 2010. Unless consumers have been hiding under a rock, the news is out there over the federal government’s proposed plans to develop new standards for light-dutyvehicles for model years 2017 to 2025.These will be tougher standards that pick up on the previously-announcedrulemaking governing greenhouse gas emissions and fuel economy standards for model years 2012 to 2016. The ones under consideration now are roughly equivalent to 47 to 62 mpg fuel economy by the year 2025. This is going to be tough for automakers to achieve, but the road there may not be entirely through electrics and hybrids.

In fact, in the Environmental Protection Agency’s (EPA’s) joint technicalassessment, the various scenarios proposed by the EPA,the National Highway Traffic Safety Administration (NHTSA)and the California Air Resources Board(CARB) show improvements being made using a range of technology pathways. While the technology pathways,says the EPA joint technical assessment, are intended to show different cost impacts if the industry were to place more or less emphasis on hybrids,plug-inhybrids, or electrics, as compared to vehicle mass reduction and use of advanced gasoline technologies, much has yet to be done. In other words, there may be room yet for not-yet-developed high-fuel efficiency gasoline engines.

Consider how much more fuel efficient some four-cylinder turbocharged engines are today compared to non-turbocharged fours. As just one example of highlyfuel-efficient turbocharged engines, the 1.4-liter turbocharged four-cylinder engine in the all-new compact 2011Chevrolet Cruze Eco(available in late 2010) is expected to deliver an EPA-estimated 40 mpg highway, compared with an estimated 36 mpg highway with the same engine and six-speed automatic transmission in Cruze LT and LTZ.